Balancing act: Chyba weighs in on topics ranging from planetary life to nuclear proliferation

Posted April 20, 2006; 03:04 p.m.

by Anne Sasso

Christopher Chyba readily admits that there is little apparent
common ground between his two career tracks: astrophysics and international
policy studies. Over the years, his diverse interests have led to some unusual
tasks, including calculating the saltiness of an ocean on one of Jupiter’s
moons and drafting the Clinton administration’s response strategy for
infectious diseases.

As unrelated as these interests seem, Chyba has carved out a career
that marries the two, balancing his commitments in both worlds.

Chyba joined the faculty in July as a professor of astrophysics and
international affairs, with teaching and research responsibilities in both the
Department of Astrophysical Sciences and the Woodrow Wilson School of Public
and International Affairs. Eventually, he also will direct the school’s Program
on Science and Global Security.

A graduate of Swarthmore College in physics, Chyba earned a second
bachelor’s degree and a master’s degree in mathematical physics as well as a
master’s degree in history and philosophy of science from Cambridge University
as a Marshall Scholar. He was awarded a Ph.D. in astronomy from Cornell
University in 1991.

Chyba then held several positions in the federal government before
returning to academia. He was a White House Fellow and served as director for
international environmental affairs with the National Security Council. He also
worked in the White House Office of Science and Technology as energy liaison
and as a consultant.

From 1996 to 1998, he taught in the Department of Planetary Science
at the University of Arizona, then moved to the SETI Institute and Stanford
University, where he was a faculty member in the Department of Geological and
Environmental Sciences and co-director of the Center for International Security
and Cooperation.

In 2001, the MacArthur Foundation awarded Chyba one of its “genius
grants,” citing his “passion for understanding life on Earth and for protecting
human civilization from self-destruction,” as well as his work focusing on “the
relationship between preparing for biological terrorism and improving public
health.”

Chyba recently discussed his career, his research and his goals at
Princeton.

Your interests range from the origins of life on other planets to
policy studies involving everything from nuclear arms proliferation to managing
the rapid explosion of biotechnology. How did you become interested in so many
questions?

I was studying theoretical physics at Cambridge University, and I
noticed that I started spending all my time in the origins of life section of
the bookstore. I was becoming very specialized in something that was enormously
beautiful. But there were all these other things I cared about, and I wasn’t
able to spend much time with them.

So I decided that if I wanted to study issues involving the origins
of life, the way to do that with a physics background was through what’s now
called astrobiology. There were very few people working in it [in the 1980s],
and one of them was Carl Sagan at Cornell University.

I wound up going to Cornell to work with Carl, because it was clear
that he had combined biology and chemistry with astronomy and planetary
science. I want to emphasize that I knew essentially nothing about any of those
fields. I had never taken an astronomy course as an undergraduate. I barely
knew what a planet was. I had some biology in my background and some chemistry,
but that’s exactly one of the things that was so appealing to me: I was going
to get to learn something about all of those things.

Were you interested in science as a kid?

I didn’t grow up intending to be an astronomer by any means. In
fact, it wasn’t one of my particular interests as a child, but I was always
interested in science. I guess like a lot of children, I was especially
interested in dinosaurs. How can you not be interested in dinosaurs?

I was a young child in the ’60s, and I think there was a different
view of scientists then, especially early on. The TV movies I watched often
portrayed scientists as people who understood the world and who also had a
positive impact on the world.

I think I absorbed that image of what scientists could be — people
who understood potentially important and profound things about the world, but
also, because of that understanding, had an opportunity to contribute to it to
make things better. I think it’s harder to find those kinds of images of scientists
in the media now.

How did public policy come into the mix?

I had a longstanding interest in international affairs, maybe not
as old as my interest in science and dinosaurs, but certainly by late grade
school. And I did my senior thesis in political science as an undergrad.

The White House Fellowship [a prestigious program that offers
people early in their careers experience working at the highest levels of the
federal government] introduced me to international security first hand. I wrote
an options paper for the deputy cabinet secretaries; I wound up chairing the
inter-agency group that drafted the U.S. response strategy for emerging
infectious diseases. I wrote the options paper that was used to decide policy
with respect to shutting down the remaining reactors at the Chernobyl site. The
White House fellowship catapults you into a host of issues.

What are your major areas of research at the moment?

You’re catching me at a time when I have just finished several big
projects. So I have the luxury of sitting back a little bit and thinking,
“Where do I really want to go next?”

On the policy side, my work mainly involves nuclear weapons or
biological weapons, proliferation and terrorism. And I do that kind of work in
different ways. I serve on committees at the National Academy of Sciences
relevant to both those areas. I occasionally work with the staff on Capitol
Hill. I’ve just been involved with the Global Pathogen Surveillance Act, which
is primarily driven by efforts to improve international disease surveillance
and response, but clearly also has a biological terrorism connection.

I’m interested in what the role of U.S. nuclear weapons is now and
what the implications are for what kind of arsenal we ought to have. In 2012,
we’ll still have around 2,000 strategic warheads. Does that number make sense?
And what should we be doing with respect to nuclear proliferation — a very
broad topic with lots of important questions to address.

And then in the biological realm, other than continuing to improve
disease response, the most pressing issue is the implication of the
biotechnology explosion, which is rapidly placing increased power into the
hands of smaller groups of the technically competent. That presents a really
different dilemma than the Cold War dilemma because, in the case of nuclear
weapons, the technologies were few, more easily controlled and required large
facilities.

In biology, none of that’s necessarily true. It’s getting
exponentially less expensive and more available to people who are merely competent
to do things that are potentially extremely dangerous. We don’t have good
models from Cold War arms control for how we’re going to deal with that world.

Will you be teaching courses on these topics?

At the Woodrow Wilson School, I’m teaching a six-week seminar on
the North Korean nuclear weapons program and the U.S. policy response. The plan
for next year is still being thought through.

I’m not a regional expert. The reason that I have something to
contribute is because I can bring the technical background with respect to the
requirements for a nuclear weapons program — and present that, I hope, to the
students in a way that will enlighten them about what’s happening and what our
options are even if they aren’t scientists or engineers.

And what kind of research are you pursuing on the astrobiology
side?

Our research continues to focus on Europa, which is one of
Jupiter’s moons where we have the best evidence for another ocean off of the
Earth. This ocean is 100 kilometers deep underneath maybe 10 kilometers of ice
on a world the size of our moon, which means the volume of the ocean is about
twice that of the Earth’s oceans.

Kevin Hand [a Stanford graduate student now with an office in the
Princeton astrophysics department] and I are looking at a number of questions.
We’re trying to understand the ocean better on the basis of spacecraft data. We
have a paper that we’re about to submit on the salt content of Europa’s ocean,
which has ramifications on how thick the ice might be and potential
astrobiological implications for life.

Also, I’m just finishing chairing a National Research Council group
called the Committee on Preventing the Forward Contamination of Mars. The U.S.
is bound by the Outer Space Treaty, plus decades of precedent, to try to avoid
carrying microorganisms on our spacecraft to Mars that could then, possibly,
contaminate Mars and interfere with the very life detection experiments that we
and other countries want to perform. And the point of this study was to ask,
given what we’ve learned about Mars and about the ability of bacteria to
survive in extreme environments on Earth, should we revise our current policies
for how clean our spacecraft have to be and the way we clean them — or not? And
if we should revise them, what should we do?

Mars is slowly looking potentially more habitable for living
organisms. There’s a frequent launch program, so we’re sending all kinds of
stuff there now. And we’ve learned that microorganisms on Earth can survive in
really harsh environments. We know that plenty of microorganisms can survive a
year in space if they’re shielded from the sun’s ultraviolet light. A set of
things have come together that suggests that this problem might be more
important and more difficult than had been appreciated.

What do you hope to accomplish here at Princeton?

This year at the Woodrow Wilson School, I co-directed the Program
on Science and Global Security, and I will become director of that program next
year or the year after. One goal I have is to further the integration of that
program with the rest of the school, in particular with international
securities studies. The program is largely a group of scientists who do
technical analysis of important security issues: nuclear issues, biological
issues, sometimes others. I would like to see that expertise even better
integrated in the Wilson School than it currently is.

Also, there’s a huge interest in astrobiology on the part of
Princeton undergraduates. But in the graduate program, we’re still just sort of
feeling our way with this topic. So one thing I’d like to do is help the
department decide what kind of astrobiology department we ought to be.

One thing that is exciting to me at Princeton is that I’m in an
astrophysics department again. There’s all this really cool astrophysics that I
haven’t spent much time with at all. Now, I’m getting to start seeing it again,
and that’s just fun. But in the meantime, there are so many international
security issues I want to stay on top of, and the Wilson School is one of the
best places in the world for doing that.